The United Kingdom’s National Security (State Threats) Bill

By Matthew Parish, Associate Editor

Wednesday 10 June 2026

The United Kingdom’s National Security Act 2023 and the wider legislative programme from which it emerged, including what was originally introduced as the National Security Bill, represent the most substantial reform of British state security law for a generation. The legislation has been presented by government as a necessary response to a radically altered security environment in which hostile foreign states increasingly employ espionage, cyber attacks, disinformation campaigns, economic coercion and covert influence operations rather than conventional military force. Critics however have argued that while the objectives may be legitimate, the breadth of the powers granted to the executive and the criminalisation of previously lawful activities create significant risks for civil liberties, investigative journalism and political dissent.

The debate surrounding the legislation is therefore not merely about national security. It is about a perennial constitutional question in British history: how far a democratic state may go in defending itself without undermining the liberties it claims to protect.

The British government justified the legislation on the grounds that existing laws were hopelessly outdated. Much of Britain’s espionage law rested upon the Official Secrets Acts of 1911, 1920 and 1939, statutes drafted during an era when intelligence threats largely involved clandestine agents stealing paper documents and transmitting them to foreign governments.

The modern threat landscape is considerably different. Cyber espionage allows hostile states to steal millions of documents remotely. Foreign governments may seek to influence elections through social media campaigns. Economic actors connected to foreign intelligence services may attempt to acquire strategic assets. Researchers, journalists, academics and businesspeople can become targets of influence operations that would have been unimaginable when the Edwardian-era espionage laws were enacted.

Government ministers have repeatedly referred to activities attributed to states such as the Russian Federation, the People’s Republic of China and the Islamic Republic of Iran. The poisoning of Sergei Skripal in Salisbury in 2018, allegations of cyber attacks against British institutions and concerns about foreign influence within universities and political organisations have all been cited as evidence that the United Kingdom required stronger legal tools.

The legislation therefore seeks to replace a framework designed for twentieth-century espionage with one adapted to twenty-first-century state competition.

One of the most significant features of the legislation is the creation of a series of new national security offences.

Traditional espionage remains criminalised, but the law substantially broadens the definition of activities that may constitute espionage. Individuals can commit offences not only by obtaining protected information but also by engaging in conduct that assists foreign intelligence activities.

The legislation introduces offences concerning foreign interference. These provisions target attempts by foreign powers to influence political processes, elections, public institutions or public discourse through covert, deceptive or coercive means.

Another innovation is the creation of offences relating to obtaining benefits from foreign intelligence services. Individuals who knowingly accept assistance or support from hostile intelligence agencies may face criminal liability even where their activities do not fit traditional definitions of espionage.

The legislation also creates offences involving sabotage. Damage to infrastructure, communications systems, transport networks or energy facilities may attract severe penalties if undertaken for purposes connected with foreign powers.

Perhaps most notably, the legislation establishes a broad concept of conduct carried out “for or on behalf of” a foreign power. This foreign power condition appears throughout the legislation and functions as a central organising principle. Activities that might otherwise be lawful can become criminal if performed under the direction, control or influence of a foreign state.

Maximum penalties are correspondingly severe. Several offences carry potential life imprisonment.

One of the most controversial elements is the Foreign Influence Registration Scheme.

The concept resembles legislation found in other countries, particularly the United States’ Foreign Agents Registration Act. Certain individuals or organisations engaged in political influence activities on behalf of foreign governments may be required to register their relationships and activities with authorities.

The government’s argument is straightforward. If foreign governments seek to influence British politics, policymaking or public debate, transparency should be mandatory.

Critics have questioned how broadly such obligations might be interpreted. Universities, think tanks, charities, research institutes and media organisations frequently receive international funding. Determining where legitimate international cooperation ends and foreign political influence begins is not always straightforward.

The concern is that uncertainty may encourage self-censorship, particularly amongst institutions that depend upon international partnerships.

A recurring criticism of the legislation concerns the extent of executive discretion.

The Act grants ministers substantial authority to designate particular states, organisations or activities as presenting elevated security concerns. Once such designations occur, additional reporting obligations and criminal liabilities may arise.

Supporters argue that flexibility is essential. Security threats evolve rapidly, and Parliament cannot realistically enact new primary legislation every time an adversarial state develops a novel tactic.

Opponents respond that broad discretionary powers reduce parliamentary oversight and concentrate authority in the executive branch. The greater the discretion granted to ministers, the greater the possibility that future governments may use those powers in ways not originally intended.

British constitutional history contains numerous examples of emergency powers introduced for legitimate reasons but later applied more broadly than initially anticipated.

Perhaps the most intense criticism has come from journalists, civil liberties organisations and media freedom advocates.

Under earlier Official Secrets legislation, prosecutors often faced substantial practical and legal obstacles when pursuing journalists who published leaked government information.

The new framework potentially expands criminal liability. Critics argue that investigative journalists receiving classified information could face increased legal exposure, particularly if authorities contend that publication benefits a foreign power or damages national security.

Government ministers have consistently denied that the legislation is intended to target legitimate journalism. They maintain that prosecutions require proof of specific elements and that public-interest reporting remains protected by broader constitutional principles and prosecutorial discretion.

Yet critics point out that reliance upon prosecutorial discretion is not the same as a statutory public-interest defence.

This distinction matters enormously. A journalist’s liberty would depend not upon an explicit legal protection enacted by Parliament but upon the judgement of prosecutors and ultimately the government.

Civil liberties groups have therefore argued that stronger protections for public-interest journalism should have been incorporated directly into the legislation.

The controversy surrounding the legislation reflects a broader tension that has characterised British governance since the beginning of the twenty-first century.

Successive governments have expanded state powers in response to terrorism, organised crime, cyber threats and foreign interference. Surveillance authorities have grown. Data retention powers have expanded. Investigatory capabilities have become increasingly sophisticated.

Each expansion has generally been justified by reference to genuine threats. Few observers dispute that foreign intelligence services actively target Britain. Few deny the reality of cyber espionage or covert influence operations.

The question is whether the cumulative effect of these measures gradually alters the balance between citizen and state.

Civil liberties advocates frequently invoke a principle articulated by the English jurist William Blackstone in the eighteenth century: that liberty is not merely freedom from arbitrary imprisonment but freedom from arbitrary government power generally.

Under this view, the danger is not necessarily how powers are used by the current government. The greater concern is how those powers might be used by future governments under different political circumstances.

A law designed to combat Russian espionage today might theoretically be employed against political activists, journalists or dissident groups tomorrow if sufficient safeguards are absent.

Britain has experienced similar debates repeatedly throughout her history.

During both World Wars, emergency powers vastly expanded state authority. During the Cold War, anti-subversion measures targeted suspected communist influence. Following the attacks of 11 September 2001 and the London bombings of 7 July 2005, counter-terrorism legislation dramatically increased surveillance and detention powers.

In nearly every case, governments argued that extraordinary threats required extraordinary measures. In nearly every case, critics warned of dangers to civil liberties.

History suggests that both sides are often partially correct. Security threats are real.

Governments genuinely require powers to address them. Yet emergency measures frequently outlive the crises that produced them, becoming permanent features of the legal landscape.

The challenge therefore lies not in choosing between liberty and security but in maintaining a constitutional equilibrium between them.

The new British National Security legislation reflects a world in which geopolitical competition increasingly occurs below the threshold of conventional warfare. Espionage, cyber attacks, influence campaigns and covert state activity are genuine challenges that democratic societies must address. The United Kingdom’s previous legal framework was undeniably antiquated and required modernisation.

Yet the legislation also illustrates the risks inherent in granting governments broader powers in the name of security. The expansion of executive discretion, the creation of wide-ranging new offences and concerns about implications for journalism and political expression have generated legitimate constitutional questions.

Whether the Act ultimately proves to be a prudent modernisation or an excessive concentration of state power will depend less upon the text of the legislation itself than upon how it is interpreted and enforced in practice. The greatest threats to liberty in democratic societies rarely arrive as explicit attacks upon freedom. More often they emerge incrementally, through well-intentioned laws enacted to address genuine dangers.

The enduring challenge for Britain is therefore the same one she has faced for centuries: defending herself against external threats without allowing the mechanisms of defence to weaken the liberties that form the foundation of her constitutional identity.